Aorta valve with expansible suturing ring



Aug; 2, 1966 M. L- WA ETAL 3,263,239

AORTA VALVE WITH EXPANSIBLE SUTURING RING Filed April 1, 1963 INVENTORS.wuss LOWELL EDWARDS ALBERT STARR AHorney United States Patent G3,263,239 AORTA VALVE WITH EXPANSIBLE SU'l'URlNG RING Miles LowellEdwards, Santa Ana, Calif., and Albert Starr,

Portland, ()reg., nssignors to Edwards Laboratories, 1116.,

Santa Ana, Calif., a corporation of Cnlifomla Filed Apr. 1, 1963, Ser.No. 269,299 13 Claims. (Cl. 3-1) This application is acontinuation-in-part of co-pending application Serial No. 49,044 filedAugust 11, 1960, now Patent No. 3,099,016.

This invention relates to an artificial valve as a prothesis in a heartto take the place of a defective natural valve.

The valve illustrated in said prior patent is a mitral valve, althoughthe general features of construction therein disclosed are applicable toboth mitral and aorta valves. The present application is directed tocertain modifications of structure in order to adapt the generalprinciples of the prior invention for utilization in an aorta valve. Thepresent invention is not limited to aorta valves, however.

An aorta valve requires special consideration in its design andconstruction because the valve body must project into the aorta itself.There is less space for such mechanism in the aorta than in the chamberof the left ventricle which contains the body of the mitral valve. Thus,although the aorta valve must handle the same quantity of blood as themitral valve, it must be smaller in its outside dimensions wherebyspecial provision must be made to avoid throttling the flow of blood.

The objects of the invention are, therefore, .to provide an improvedartificial valve, to provide an improved aorta valve, to provide a valvefor implantation directly in the entrance to the aorta below thecoronary arteries and to provide a sewing ring for an aorta valve ofconical skirt shape and made of expansile material which can change indiameter as variations in the blood pressure expand and contract thediameter of the aorta.

The present valve is generally similar to the mitral valve mentionedabove but incorporates certain special features to increase the size ofthe port opening relative to the size of the valve body and tofacilitate attachment of the sewing ring to the heart tissue directly atthe entrance to the aorta. Other features and advantages will becomeapparent from the following detailed description of the preferredembodiment illustrated on the accompanying drawing. All variations andmodifications within the scope of the appended claims are included inthe invention.

In the drawing:

FIGURE 1 is a longitudinal sectional view of a valve embodying theprinciples of the invention;

FIGURE 2 is a top plan view of the valve in reduced scale with partsbroken away;

FIGURE 3 is a bottom plan view of the valve; and

FIGURE 4 is a section of a human heart, showing the present valveinstalled therein.

The valve comprises an integral body member made of a suitable materialwhich is compatible with the human body. Various types of non-toxicplastic may be used, such as Dupont Lucite acrylic resin, Rohrn & HaasPlexiglas acrylic plastic, and the like. Metal is preferable to plastic,however, the preferred material being an alloy known as Stellite whichis non-corrodible and inert to blood and living tissue. Stainless steelmay also be used.

The entire body 10 comprising a base or port ring portion 11 and a cageportion 12 is preferably made in one piece either as a molding or acasting. The base ring defines a valve port having an internal sphericalseat 13 corresponding to the curvature of silicone rubberball 15. Inorder to provide as large a port as possible, the maximum inclination ofseat 113 from the vertical is 15 as right atrium 48.

3,263,239 Patented August 2, 1966 indicated by the angle at 16. In orderto prevent any possibility of the ball escaping through the port,special retention means may be provided. These comprise three inwardlyand downwardly directed stop fingers .17. Preferably, these stops aredisposed between the three legs of cage 12. The stops may be omittedwhen the dimensions and angular relationships are such as to prevent theball from escaping through the port in use. The resilient ball isinserted in the cage by squeezing it between two of the cage legs.

The outside of base ring 11 forms an annular channel having a nearlyhorizontal bottom wall 21 having a slight downward inclination and anupwardly inclined top wall 22. In the illustrated embodiment theinclination of wall 22 is approximately 45. A flexible sewing ring 25 ismounted and secured in channel 20.

Sewing ring 25 preferably comprises a piece of knitted Teflon clothhaving a mid-portion clamped in the channel 20 by a one-piece splitspreader ring '26 of suitable material such as Teflon plastic. Thespreader ring 26 is itself channel-shapcd in cross section with anexternal shape corresponding generally to the shape of channel 20 andhaving an outwardly facing channel 27. The spreader ring is clampedagainst at least one thickness of the cloth by a winding 28 of Teflonthread which is wound under tension in chancl 27. When the body member10 is made of metal, all the other parts should be non-metallic toprevent electrolysis.

The lower end portion 30 of the cloth is folded back on upper portion 32and stitched with Teflon thread 31 to a folded back upper end portion 33of the cloth as shown. This produces a bight portion at 35 whichencloses a resilient silicone rubber ring 36. The cloth is formed into asmoth frusto-conieal shape -by a pressing operation. This results in asleeve of inverted flaring skirt shape which makes an angle of about 22'with the vertical as indicated by the angle 40. Rubber ring 36 serves asan extens-i-le element to stiffen the free upper end of the skirt andhold it extended in circular configuration in plan view. The folded endportions at 30 and 33 abut each other to form a pad having a thicknessof at least three layers of cloth. This provides secure anchorage forthe sutures. Rubber ring 36 is not necessary in small sizes of the valveas then the cloth will hold itself in conical shape without a separateextensi-le element.

FIGURE 4 shows the manner of installing the valve in a human heart 45.The heart has a left atrium 46. a left ventricle 47, a right atrium 48and a right ventricle 49. A mitral valve 50 prevents reverse flow ofblood from left ventricle 47 back into left atrium 46 and a mitral valve51 prevents reverse flow from right ventricle 49 back into Blood flowsfrom left ventricle 47 through an aorta valve into aorta 56 from whenceit is distributed into main arteries 57 and others leading to differentparts of the body. The aorta normally makes a sharp bend between theheart and the arteries 57, as shown.

The present valve is usually installed by making an incision 52 throughthe outside of this bend which provides access for surgical treatment ofthe natural aorta valve. The natural aorta valve parts are removed andthe present valve is installed in the same location. The sewing ring 25is secured to living tissue at the entrance to the aorta by threads orsutures 53 with the cage 12 extending up into the aorta. The suturing isfacilitated by the act-ion of extensile rubber ring 36 which holds theupper free end of the skirt portion of the sewing ring expanded intocontact with the inside of .the aorta wall, as shown. Normally, theaorta increases in size at this point whereby the flare of the skirt ofthe sewing ring conforms generally. with the taper of the aorta.

The combination of upwardly inclined wall 22, the top surface of whichconforms to the flow pattern of the blood, and tlte spacing of stopfingers l7 staggered between cage legs 12 provide maximum flow aroundthe legs 12. This minimizes tlte tendency toward a shadow in the flowpattern between the legs and the sewing ring where clots could form.Usually abouLtwo-thirds of tlte sutures may be tied against the innersttrface of the conical sewing ring adjacent to the legs of the cage.These suture knots are inclined to excite the clot formation. Thestaggered arrangement of stop fingers and cage legs is to avoid aconcentration of impediments in the flow through the valve. This providemaximum washing of blood around the cage legs to the area directlybetween the leg and the inside of the sewing skirt to minimize tltepossibility of clot formation at that area.

It is to be noted that the valve is installed below the coronaryarteries 55 so that it functions in the circulatory system the same asthe natural aorta valve.

A most important feature of the valve is the expansile sewing ringbrought about by the nature of the cloth used and the rubber ring placedin the upper extremity of the skirt. It aids the surgeon in selection ofa valve. Although measuring devices are used, they are not precise and acertain amount of flexibility here is important.

Another point is that the valve is installed when the aorta is at zeropressure. When in use, the pressure extends the aorta diameter and thesewing ring must expand accordingly.

There is also the important point that the rttbber rittg being placed atthe upper extremity of the skirt causes the pressure difference acrossthe valve, when the valve is in a closed position, to be sealed at thelocation of the rubber ring forcing the entire area of the skirt outwardagainst the aorta wall, preventing wrinkles. This action is very ntuchlike the seal in the leather cup of a bicycle tire pump.

Having now described our invention and in what manner the same may beused, what we claim as new and desire to protect by Letters Patent is:

1. A heart valve comprising a port ring, a movable valve membercooperating with the port in said ring, an outwardly facing annularchannel in said port ring, said channel having a bottom side wallinclined slightly downward from the plane of said ring and a top sidewall inclined upward at a much greater angle front said plane, anannular sewing ring comprising an upwardly flaring skirt of flexiblematerial capable of being pierced by a needle and suture, and meansclamping the lower end of said skirt in said channel.

2. A heart valve comprising a port ring, a movable valve membercooperating with the port in said ring, and an annular sewing ringsecured to said port ring, said sewing ring comprising an upwardlyflaring skirt of flexible material capable of being pierced by a needleand suture, said skirt comprising multiple layers of cloth formed tofrusto-eonical shape.

3. A heart valve comprising a port ring, a ball cage on the upper sideof said port ring, a ball in said cage coopcrating with the port in saidring, a plurality of stop fingers projecting inwardly from said ring toretain said ball in said cage, and an annular sewing ring secured tosaid port ring, said sew-ing ring comprising an upwardly flaring skirtof flexible material capable of being pierced by a needle and suture.

4. A heart valve as defined in claim 6, said cage com prising aplurality of spaced legs extending from said port ring and said stopfingers being staggered between said legs.

5. A heart valve comprising a port ring, a ball cage cxtcndittg upwardlyfrom the upper side of said ring, a ball in said cage, stop fingersprojccting'inwardly front said ring to retain said ball in said cage, anoutwardly facing annular channel in said ring, a piece of cloth havingits ntid-portion secured in said channel, upper and lower ends of saidclotlt projecting front said channel being stitched together and formedinto a frusto-conical skirt flaring upwardly and outwardly from saidchannel, and a rubber rittg enclosed itt a fold in the free upper ettdof said skirt.

6. A heart valve comprising a port ring, a ball cage extending upwardlyfront the upper side of said ring. a ball in said cage, a flexible skirtmade of material capable of being pierced by a needle and suture, saidskirt having its lower end secured about said ring and having a freeupper end extending above said ring, and an extensilc flexible ringsecured in said upper end of said skirt.

7. A heart valve comprising a port ring, a ball cage on one side of saidring, a ball in said cage, and a flexible skirt made of ntatcrialcapable of being pierced by a needle and suture, said skirt having asmall lower end secured to said ring and flaring outwardly and upwardlyto a free upper end surrounding said cage above said ring.

8. A heart valve comprising a circular valve body having a valve member,a clotlt having a portion disposed against said body, means sccttringsaid portion of said clotlt around said body and a ring of soft,resilient material enfolded in other portions of said cloth inoutstanding position from said body.

9. A heart valve comprising a circular valve body having a valvententbcr, an outwardly facing channel around said body, a cloth having aportion disposed in said channel, means securing said portion of saidcloth itt said channel, and a soft rubber ring enfolded in otherportions of said cloth in otttstanding position front said body.

10. A heart valve prosthesis comprising a substantially rigid circularvalve body having a valve member and a cloth sleeve having a lower endsurrounding and secured to said body, said sleeve extending axially ofthe valve body and having a substantially circular free upper endsurrounding said valve member, spaced radially therefront and at asubstantial distance above said secured end.

11. A heart valve as set forth in claim 10 including circumferentiallyspaced stop fingers projecting inwardly from the side of said valve bodyopposite said valve member.

12. A lteart valve as defined in claim 10, said valve body having anannular channel therearound, and means secur ing said lower end of saidcloth sleeve in said channel.

13. A heart valve as defined in claim 10 ine-lding a soft rubber ringenfolded in said upper end of said sleeve.

References Cited by the Examiner UNITED STATES PATENTS 1,890,594 12/1932Turner 273-653 2,682,057 6/1954 Lord 3-1 2,688,979 9/1954 Kendrick137-5251 X 3,099,016 7/1963 Edwards 3-1 3,143,742 8/1964 Cromie 3-1RICHARD A. GAUDET, Primary Examiner.

R. L. FRINKS, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,263,239 August 2, 1960 Miles Lowell Edwards et a1.

It is hereby certified that error appears in the above numbered patentrequiring correction and that the said Letters Patent should read ascorrected below.

Column 3, line 13, for "provide" read provides line 67, for the claimreference numeral "6" read 3 Signed and sealed this 1st day of August1967.

(SEAL) Attest:

EDWARD M. FLETCHER, JR. EDWARD J. BRENNER Ilvfiting Officer Cmnmiseinnvrof Pzuvnis

10. A HEART VALVE PROSTHESIS COMPRISING A SUBSTANTIALLY RIGID CIRCULARVALVE BODY HAVING A VALVE MEMBER AND A CLOTH SLEEVE HAVING A LOWER ENDSURROUNDING AND SECURED TO SAID BODY, SAID SLEEVE EXTENDING AXIALL OFTHE VALVE BODY AND HAVING A SUBSTANTIALLY CIRCULAR FREE UPPER ENDSURROUNDING SAID VALVE MEMBER, SPACED RADIALLY THEREFROM AND AT ASUBSTANTIAL DISTANCE ABOVE SAID SECURED END.